Amana AMSS920803BN Error Code No LED Signal: No 115 Volt Power / No 24 Volt Power
What Does Code No LED Signal Mean?
When the diagnostic LED on your Amana AMSS920803BN control board shows no signal, it means the integrated control module is not receiving electrical power. The furnace cannot operate at all in this state because the control module manages every function from ignition to the blower motor.
The most common cause is a tripped circuit breaker or blown fuse at your electrical panel. The second most likely cause is the furnace disconnect switch or door switch being open. The disconnect switch is typically located on or near the furnace, and the door switch prevents operation when the access panel is removed.
If both the breaker and switches are fine, the control module itself may have an internal fault. This is less common but would require a technician to diagnose and replace the module. Note that LED flash codes will cease if power is interrupted through the disconnect or door switch, so always verify these are properly engaged.
Common Causes
How to Fix It: Check the Circuit Breaker and Power Switches
What You'll Need
Steps
- Turn off power and gas supply as a precaution Before investigating, turn the gas shutoff valve near the furnace to the OFF position (perpendicular to the pipe). If you smell gas at any point, leave immediately and call your gas company.
- Check the circuit breaker Go to your home's main electrical panel and find the breaker labeled for the furnace or HVAC system. If it is in the middle (tripped) position, flip it fully to OFF first, then back to ON. Some panels have fuses instead of breakers — check if the furnace fuse is blown and replace it with one of the same amperage.
- Check the furnace disconnect switch Look for a standard light switch on or near the furnace, usually on the side of the unit or on a nearby wall. Make sure it is in the ON position. This switch is easily mistaken for a regular room light switch and may have been turned off accidentally.
- Verify the access panel door switch Make sure the furnace access panel is properly seated and latched. The door switch prevents the furnace from operating when the panel is removed or not fully closed. Press the panel firmly until it clicks into place.
- Restore gas and verify power Turn the gas supply valve back to ON (parallel to the pipe). Check the furnace control board through the access panel — the LED should now be lit with a steady light, indicating normal operation. Set your thermostat to call for heat and confirm the furnace starts.
When to Call a Professional
Contact a licensed HVAC technician if:
- The circuit breaker trips again immediately after resetting
- The power switch is on and the breaker is not tripped, but the LED remains off
- The access panel is properly installed but the door switch does not engage
- You notice a burning smell or signs of electrical damage near the furnace
✓ Verified against manufacturer service manual — March 2026